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    i really need some practise on those quadratics in disguise in C1.
    the ones that i am talking about are like this: 3x^2/3 + x^1/3 - 2 = 0

    does anyone know any places that has a lot of questions like these becasue i really need some practise on them.
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    You can make up your own, solve them, then check here
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    Here are some you could try:

    x^{-2}-3x^{-1}-4=0

    4(x-1)^2+4(x-1)=3

    x^3-2x^{3/2}+1=0

    2x-6\sqrt{x}+4=0

    3(x^2-\frac{1}{2})=2-2(x^2-\frac{1}{2})^2

    x+x\sqrt{x}-6\sqrt{x}=0 (hint: consider when x=0, then for x non-zero divide through by root x)
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    I don't understand why they are in disguise? Just out of curiousity? They look normal to me but I might remember C1 differently.
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    They're 'in disguise' in that they aren't in the form ax^2 + bx+c, but require a substitution to get them there.
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    a[f(x)]^{2n}+b[f(x)]^n+c=0\Longleftrightarrow [f(x)]^n=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}

    simple as
 
 
 
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Updated: December 19, 2010
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